REVENUE AND SEGMENT INFORMATION - Significant expense categories (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
SEGMENT INFORMATION
Total research and development	$ 918	$ 1,826	$ 3,842	$ 5,592
Selling, general and administrative
Total selling, general and administrative	8,610	8,260	26,209	26,097
Capital expenditures of the segment			100	200
Single reportable segment
SEGMENT INFORMATION
Clinical expenses	719	936	2,510	3,499
Other research and development expenses	199	890	1,332	2,093
Total research and development	918	1,826	3,842	5,592
Selling, general and administrative
Royalty expense	285	354	826	1,594
Stock-based compensation	376	843	1,435	2,792
Legal, financial and consulting	1,061	824	3,063	2,325
Other general and administrative	6,888	6,239	20,885	19,386
Total selling, general and administrative	$ 8,610	$ 8,260	$ 26,209	$ 26,097

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Amount of expense for research and development. The amount is net of grant income and grant income-related expenses.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of general and administrative expense classified as other.

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A fee charged for services from professionals such as doctors, lawyers and accountants. The term is often expanded to include other professions, for example, pharmacists charging to maintain a medicinal profile of a client or customer.

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Amount of expense for research and development. Excludes cost for computer software product to be sold, leased, or otherwise marketed, writeoff of research and development assets acquired in transaction other than business combination or joint venture formation or both, and write-down of intangible asset acquired in business combination or from joint venture formation or both, used in research and development activity.

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Amount of expense related to royalty payments under a contractual arrangement such as payment for mineral and drilling rights and use of technology or intellectual property.

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Amount of expenditure for addition to long-lived assets included in determination of segment assets by chief operating decision maker (CODM) or otherwise regularly provided to CODM. Excludes expenditure for addition to financial instrument, long-term customer relationship of financial institution, mortgage and other servicing rights, deferred policy acquisition cost, and deferred tax assets.

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